title: A pair of circularly permutated PDZ domains control RseP, the S2P family intramembrane protease of Escherichia coli.
abstract: The sigma(E) pathway of extracytoplasmic stress responses in Escherichia coli is activated through sequential cleavages of the anti-sigma(E) protein, RseA, by membrane proteases DegS and RseP. Without the first cleavage by DegS, RseP is unable to cleave full-length RseA. We previously showed that a PDZ-like domain in the RseP periplasmic region is essential for this negative regulation of RseP. We now isolated additional deregulated RseP mutants. Many of the mutations affected a periplasmic region that is N-terminal to the previously defined PDZ domain. We expressed these regions and determined their crystal structures. Consistent with a recent prediction, our results indicate that RseP has tandem, circularly permutated PDZ domains (PDZ-N and PDZ-C). Strikingly, almost all the strong mutations have been mapped around the ligand binding cleft region in PDZ-N. These results together with those of an in vitro reaction reproducing the two-step RseA cleavage suggest that the proteolytic function of RseP is controlled by ligand binding to PDZ-N.
authors.affiliation: Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Inaba
authors.forename: Mamoru
authors.initials: M
authors.lastname: Suzuki
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Maegawa
authors.forename: Shuji
authors.initials: S
authors.lastname: Akiyama
authors.forename: Koreaki
authors.initials: K
authors.lastname: Ito
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Akiyama
mesh_terms: D018360:Crystallography, X-Ray / Q000379:methods; D010450:Endopeptidases / Q000737:chemistry* / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D005786:Gene Expression Regulation; D006639:Histidine / Q000737:chemistry; D008024:Ligands; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008957:Models, Genetic; D008958:Models, Molecular; D008968:Molecular Conformation; D009154:Mutation; D019897:Periplasm / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D013997:Time Factors
chemical_list: D029968:Escherichia coli Proteins; D008024:Ligands; D008565:Membrane Proteins; D006639:Histidine; D010450:Endopeptidases; C440001:RseP protein, E coli